Luminaires with automated and remotely controllable functionality are well known in the entertainment and architectural lighting markets. Such products are commonly used in theatres, television studios, concerts, theme parks, night clubs and other venues. A typical product will commonly provide control over the pan and tilt functions of the luminaire allowing the operator to control the direction the luminaire is pointing and thus the position of the light beam on the stage or in the studio. Typically, this position control is done via control of the luminaire's position in two orthogonal rotational axes, usually referred to as pan and tilt. Many products provide control over other parameters such as the intensity, color, focus, beam size, beam shape, and beam pattern. The beam pattern is often provided by a stencil or slide called a gobo which may be a steel, aluminum, or etched glass pattern. The products manufactured by Robe Show Lighting such as the Robin MMX Spot are typical of the art.
The optical systems of such automated luminaires may be designed such that a very narrow output beam is produced so that the units may be used with long throws or for almost parallel light laser like effects. These optics are often called Beam′ optics. To form this narrow beam with the large light sources in the prior art, the output lens either needed to be very large with a large separation between the lens and the gobos or of a short focal length and much closer to the gobos
FIG. 1 illustrates a multiparameter automated luminaire system 10. These systems commonly include a plurality of multiparameter automated luminaires 12 which typically each contain on-board a light source (not shown), light modulation devices, electric motors coupled to mechanical drive systems, and control electronics (not shown). In addition to being connected to mains power either directly or through a power distribution system (not shown), each luminaire 12 is connected in series or in parallel to data link 14 to one or more control desks 15. The luminaire system 10 is typically controlled by an operator through the control desk 15. Control of the automated luminaires 12 is effectuated by electromechanical devices within the luminaires 12 and electronic circuitry including firmware and software within the control desk 15 and/or the luminaires 12. In many of the figures herein, important parts like electromechanical components such as motors and electronic circuitry including software and firmware and some hardware are not shown in order to simplify the drawings so as to teach how to practice the inventions taught herein. Persons of skill in the art will recognize the need for these parts and should be able to readily fill in these parts.
In prior art luminaires, lamps with extremely small light sources have been developed. These lamps often use a very short arc gap, of the order of 1 millimeter (mm), between two electrodes as the light producing means. These lamps may be used for producing a very narrow beam as their source etendue is low, and the size of the lenses and optical systems to collimate the light from such a small source can be substantially reduced. However, the short arc and small light source coupled with the short focal length, and thus large light beam angles, of the reflector also tend to produce substantial amounts of unwanted and objectionable spill light which can escape between gobos or around the dimming shutters. Further, arc lamps require very high voltages in order to ignite the lamp, and can produce dangerous amounts of heat and ultraviolet (UV) energy, which needs to be filtered out. In recent times, LED emitters have become available that are small enough and powerful enough to be used in this kind of luminaire. However, they need improvements to their design to improve the homogenizing and collimation of their optical systems.
There is an increased need for an improved automated luminaire utilizing an LED light source capable of producing both very narrow output beams and of projecting images.